The present invention relates to a new type of organic compound which in a number of its embodiments has a positive dielectric anisotropy and which presents a stable liquid crystal state over a wide temperature range. It can be used for a twisted nematic liquid crystal display device of the more common types as well as for those employing the guest-host effect. For a long life, it is necessary that the liquid crystal compound be stable against attack by external factors such as water, air, light and the like. Furthermore, it is necessary that the compositions utilizing liquid crystal display devices remain in the nematic state over a wide temperature range, generally it being necessary that the nematic state temperature range include room temperature. Also, the material should be colorless in addition to being chemically stable.
The compounds of the present invention possess the requisite properties making them suitable for use in liquid crystal display devices whether of the more common type or involving the guest-host effect or multiplexing.